java基础4--面向对象下（几道练习题）

一、

/*定义一个ClassName接口，接口中只有一个抽象方法getClassName（）；设计一个
类Company。该类实现接口ClassName中的方法getClassName（）。功能是获取该类的
名称；编写应用程序使用Company类*/

interface ClassName{
String getClassName();
}

class Company implements ClassName{
public String getClassName(){
return "Company";
}
}

public class Test6_1{
public static void main(String[] args){
System.out.println(new Company().getClassName());
}
}

二、

/*建立一个人类Person和学生类Student。功能要求如下：
（1）Person中包含4个私有的数据成员name、addr、sex、age。分别为字符串型、字符型和整型。
用一个4参构造方法、一个2参构造方法、一个无参构造方法、一个输出方法显示4种属性。
（2）Student类继承Person类、并增加成员math、english存放数学和英语成绩。一个6参构造方法、
一个2参构造方法、一个无参构造方法并重写输出方法用于显示6种属性。*/

class Person{
private String name;
private String addr;
private char sex;
private int age;

public void setName(String name){
this.name = name;
}
public void setAddr(String addr){
this.addr = addr;
}
public void setSex(char sex){
this.sex = sex;
}
public void setAge(int age){
this.age = age;
}

public Person(String name,String addr,char sex,int age){
this.setName(name);
this.setAddr(addr);
this.setSex(sex);
this.setAge(age);
}
public Person(String name,int age){
this.setName(name);
this.setAge(age);
}
public Person(){}

public String getInfo(){
return "name: "+this.name+
"; addr: "+this.addr+
"; sex: "+this.sex+
"; age: "+this.age;
}

public void say(){
System.out.println(this.getInfo());
}
}

class Student extends Person{
private int math;
private int english;

public void setMath(int math){
this.math = math;
}
public void setEnglish(int english){
this.english = english;
}

public Student(String name,String addr,char sex,int age,int math,int english){
super(name,addr,sex,age);
this.math = math;
this.english = english;
}
public Student(String name,int age){
super(name,age);
}
public Student(){};

public String getInfo(){
return super.getInfo()+
"; math: "+this.math+
"; english: "+this.english;
}

public void say(){
super.say();
}
}

public class Test6_3{
public static void main(String[] args){
Person per1 = new Person("lisi",27);
Person stu1 = new Student("zhangsan","huiyang",'M',20,68,91);
Student stu2= new Student("hxq","huizhou",'M',20,98,82);
per1.say();
stu1.say();
stu2.say();
}
}

三

/*定义员工类，具有姓名、年龄、性别属性，并具有构造方法和显示数据方法。定义
管理层类，继承员工类，并有自己的属性职务和年薪。*/

abstract class Employee{
private String name;
private int age;
private String sex;

public Employee(){}
public Employee(String name,int age,String sex){
this.setName(name);
this.setAge(age);
this.setSex(sex);
}

public void setName(String name){
this.name = name;
}
public void setAge(int age){
this.age = age;
}
public void setSex(String sex){
this.sex = sex;
}

public String getInfo(){
return "name = "+this.name+
"; age = "+this.age+
"; sex = "+this.sex;
}
public abstract void print();
}

class Managemen extends Employee{
private String position;
private int annualPay;

public Managemen(){}
public Managemen(String name,int age,String sex){
super(name,age,sex);
}
public Managemen(String name,int age,String sex,String position,int annualPay){
super(name,age,sex);
this.setPosition(position);
this.setAnnualPay(annualPay);
}

public void setPosition(String position){
this.position = position;
}
public void setAnnualPay(int annualPay){
this.annualPay = annualPay;
}

public String getInfo(){
return super.getInfo()+
"; position = "+this.position+
"; annualPay = "+this.annualPay;
}
public void print(){
System.out.println(this.getInfo());
}
}

public class Test6_4{
public static void main(String[] aegs){
Managemen mgm = new Managemen("hxq",27,"man","manager",100000);
mgm.print();
}
}